Packaging of coffee



Patented Nov. 11, 1947 UNITED STATES ,PA'TENT' OFFICE PACKAGING F COFFEE AbrahamSidney Behrman, Chicago, Ill.

No Drawing. Continuation ofapplication Serial No. 456,693, August 29, 1942. This application August 14, 1944, Serial No. 549,481

Claims. 1

This invention relates to the packaging of foods, and'is concerned especially with packaging, in gas imperviou containers, of foods which give off gases after packaging with consequent strain on and possible destruction of the package. I

More specifically, the invention is directed to improvements in the packaging of roasted, freshly ground coffee, which gives off such substantial amounts of carbon dioxide gas after packaging that the pressure of the gas thus liberated may cause serious bulging or even rupture of gas impervious bags, canisters, or other containers used in the packaging.

A principal object of the invention is the provision of a method for preventing the bulgingor rupture of gas impervious containers in which roasted freshl ground coffee is packaged.

Another important object of the invention is the provision of an improved gas impervious, vapor transmission proof, package for roasted freshly ground coffee which will not bulge or rupture due to the pressure of carbon dioxide gas given oil" by the coffee. a

A further object of the invention is to provide a method of packaging, and an improved package, which will improve the keeping qualities and flavor of coffee.

These and other objects of my inventionwill become apparent on further reading of the following specification and claims.

This is a continuation of my application for patent Serial No. 456,693, filed August 29, 1942.

In the marketing of ground coffee the general practice has been to roast the coffee, grind it and package it almost immediately thereafter in order to retain as much as possible of the aroma and flavor; and at the same time avoid oxidation by atmospheric oxygen. Optimum results inthese directions suggest the use of airtight, gas impervious, containers. Unfortunately, however, immediate packaging in such containers results in the building up,by the carbon dioxide which escapes from the freshly ground coffee, of pressures sufficiently high to put a severe strain on the container. When, for example, the container is a flexible bag, which is desirable, particularly if it can be made with paper, the pres sure may cause objectionable bulging and even bursting. This, I believe, is the principal reason that gas impervious bags have not gone into general use for the packaging of freshly ground roasted coffee, even in these days of scarcity of steel and tin.

reaction, but to a simple escape of the gas which has been held in the cells of the coffee bean. In the course of ten hours, or thereabouts, the pressure in a gas impervious package of freshly ground roasted coffee builds up to about 6 pounds per square inch, the curve of pressure development flattening out after these first few hours.

Several methods have been proposed to overcome the difiiculties caused by this development of pressure within gas impervious packages. In connection with the use of glass jars and tin cans, vacuum packing has been practiced. In such packed coffee is opened. a hissing noise is heard tainer toleave space for expansion. Even so, the

pressure of the liberated carbon dioxide more vide containers with mechanical escape valves pears to be due, not to any continuing chemical but this has not worked out successfully in practice. So far the use of gas impervious bags for the packaging of coffee has not been practical.

The basic principle of my invention involves the provision, within the package, of a reagent which will combine with the carbon dioxide and thus lower its vapor pressure sufficiently to prevent objectionable strain on the container, whether the container be a metal can, a flexible bag, or other form of gas impervious or vapor transmission proof enclosure. While my invention is not limited to the use of a particular reagent, I have found especially effective the anionexchange materials such as the m-phenylene diamine formaldehyde resins and the aniline formaldehyde resins of Adams and Holmes (Chemistry and Industry, January 1935), or biguanidineformaldehyde synthetic resins (Swain'U. S. Patent No. 2,251,234), or equivalent materials.

The reagent may be utilized in a wide variety of ways, therefor my invention is not limited to any specific form, physical state, or manner of presentation, or exposure, of the reagent. Materials of the anion-exchange class were first described by Adams and Holmes in Chemistry and Industry in January, 1935, and comprise generically synthetic resins formed by condensing an aromatic amine, such as m-phenylene diamin j free i h ox e-1.

a In c i eo tm y nv nfiw the anion exchang E resins eithenin the liquid,

. or aniline, with an aldehyde, such as formaldehyde. Among other substances having similar properties which have been described in the patent literature are modified m-phenylene diamine resins, a biguanidine formaldehyde resin, oxidized dyestuffs such as "aniline black, and certain metallic oxides, andhydroxides =(e. n d a m nums and h dr x d s). particularly in gel form. Certain materials of this general type have come into rather wide, spread commercial use for the removal of free acids from liquids, particularly in the prepare tion, or by any other appropriate procedure, depending on the particular resin involved.

In some cases it will be found desirable to treat the anion-exchange substance, before final washing, drying and insertion in the package, with a solution of sodium or potassium hydroxide, in

.orderh to increase the supply of hydroxyl ions,

' 'f andfltcifremove traces of odor.

tion of highly purified water equivalentto ,dis tilled water in its low dissolved solids content In th preparation of such highly purified-wa ter, the water is usually-firstsubjeoted toaI; hydrogen exchange treatment whereby the salts in the water, e. g. the alkali metal and alkalin e,-

earth sulfates and chlorides, are converted to ,thev corresponding. ire. mineral ..aci ds, suoh as sulfuricand .hydrochlorijc' acids; the the' n subjected-tdtrearme tgwith mv .a lQXi X- cane-m e i swash t k -raised ret iinsth w e acre- 5 w i f h i fi i t aw-1 .1 r n-exc an ma r al i s n -rat 'llsolution of; a strong acid, such as sulfur fn hydrochloric and the; exhausted amen-f exchange ar eria s reg e at d h;.a.- 9 l in at a a el as ch s odiumiqrl.p tessiumw vd e q carb n te his. b a

o h .am qaium .Theche ic assess. wiu fh emailnucleus of; the

. free .anionee'xchangef materials which have found. greatest favor are fthe synthetic resins. These e I ma e. dr h nd t Par b r ct n easo o'ithe. avprp r a yrs s s unde rop- :conditions causing thereaction mixturetosetw to a gel, and drying the gel o ,j,

s c mor gel, ordried form. ,In;the. ,dried ma hemat l. ayb sed i st mpa a f n I QW". der or coarser-particles;enclosed in.,apelimeable paperstructureyfi 1 3, b nr sm nst l th a, comm i l y a le. l n onr xchane {naterial; indrygranular iorm g in Lthe ;;propo,rtion 1 ne-h o n t er W1. film-h f P n s airtight j icontainer, prevented conipletely the deveiopmentoianypressurezwithim the container, whereas in. the absence of such material. Ples-' Reference has already been made to the anionexchange properties of certain metallic oxides and hydroxides. --'ides-are' 1 especially active in this respect.

Ferric and aluminum hydrox- In utilizing thes substances for carrying out my invention, they may be employed in dried form "(as previouslydescribed for the synthetic resinsl jftheyinay be incorporated into the carrier in the form "ofundried gelatinous precipitate iferrned, for example, by reacting solutions of ferric chloride and sodium hydroxide, or aluminum sulfateand ammonium hydroxide) which {is subsequently "dried; or they may be formed .inj'si tu, b'y impregnating the carrier first with one reagent and then theother, and; subsequentl'y drying.

It'is ob ions that the amount of any typelof reac ng; materialiemployed for carbon dioxide removal, within a-vapor transmission proof package shou i d be; adjusted as experience dictates. The

(ideal condition oi course, isto employ just enough of the reagent toremoveall of the carbon, dioxide l bera ed. andat the rate of liberation, in order to avoid a condition of either positive or negative pressure. on thec'ontainer. Economy of th reegent is ,aided by extending its-surface as much .as possible ,-an d making this surface readily accessible. ,The form,-.1size and location of themserts orl carriers containing the reagent are all v if actors to bec0nsid,ered. Instead of incorporating the reagent in,:or, with, an insert carrier, it .may. be desirable-to coat theinner wall orwalls ,of gthe eontainer -.with van anion-exchange substance in its liquid reaction mixture state prior .togelation; -.-The coating:- obviously will be dried of this invention it is not necessaryto add. agents rpriorqto insertion :of, thewcoifee.v In preparing anioi'i-exchange,materials for. use in the process qdesignedtoimpart the mechanical strengthand -materia1s iS-'thusavoided. an example of a flexible. material suitable stability required when'such materials are to be subjected to regeneration and ;reuse. The diluting effect of such agents on the activity of the i for; use in-thepackaging. of coffee by therprocess -ofi this invention Isuggest an inner liner of rub- :ber hydrochloride laminated to glassine paper by a'rmicro crystalline wax 'adhesive.=' The adhesive addsito.thegasimpervious characteristics of the laminated sheet, the .rubber chloride liner can be'heatseaied, which is of. value in forming'and sealing 'th'e'containerfand the glassine forms a "protectivecovering that can be printed attrace x't e .e -'''i- H sures ..,developed under the-same conditionspt;

test thatzwer suiiicientto balloon andburst the "best-kind of-flexible icont alnertwith whicngl. am

, familiar, and tow exert objectionable internal strains canon-flexible containers, I

i :sAs previously; mentionedfi the anion-exchange q substance may likewisepbe, used: inathe; form of f the aundried -gels The advantage .here :isthat a==larger amount: of the materialjmay sometimes :be incorporated ini'th'e carrierin-this way, where such 5 larger amount is desirable. @Gelation; may" t be brought about by concentration, by acidificabe'cornefamiliariwith the'inve'r'ition All modi- Other applications anid'me'an's of application of the principle of myyinvention will naturally Suggest themselves to those skilled in the artas they :ificati'ons.jandi extensions .of; the invention are 1 Lclaim-z 1 jdeemedias .being, within the scope of the accompanying claims.

1. A method of packaging freshiy ground roastcdzcoffee-zwhlch-.comprisesplacing the coffee in a bag formed .of gas. impervious material, disposing within the bag a synthetic resin having roasted coffee which comprises placing the coffee in a bag formed of gas impervious material, disposing within the bag a fabric impregnated with a synthetic resin having anion-exchange properties and immediately thereafter sealing the open end of, the bag.

3. A method of packaging freshly ground roasted coffee which comprises placing the coffee in a gas impervious container, within which is disposed a substance having anion-exchange properties, and thereafter sealing the open end of the container.

4. A package comprising freshly ground roasted coffee and a synthetic resin having anion-exchange properties sealed within a gas impervious bag.

5. A method of packaging freshly ground roasted coffee which comprises placing the coffee in a gas impervious container, placing therein an anion-exchange material capable of removing carbon dioxide from. the package and thereafter sealing the open end of the container.

ABRAHAM SIDNEY BEHRMAN.

REFERENCES cI'rEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,333,524 Wilson Mar. 9, 1920 1,528,790 Rector Mar. 10, 1925 265,609 Johnston Oct. 10, 1882 1,584,903 Supplee May 18, 1926 1,532,831 Mastin Apr. '7, 1925 2,106,486 Kirkpatrick Jan. 25, 1938 2,298,545 Waters Oct. 13, 1942 2,225,810 Waters Dec. 24, 1940 2,102,716 Berch Dec.'21, 1937 OTHER REFERENCES Mellor, Modern Inorganic Chemistry, Longmans Green & Co., London, 1922, page 886. (Copies in Division 63.)

Certificate of Correction Patent No. 2,430,663. November 11, 1947. ABRAHAM SIDNEY BEHRMAN It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Column 2, line 13, strike out the 'WOIdS packed cofiee is opened, a hissing noise is heard, and insert instead the Words and hyphen packing it is customary to use an oversized con-; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 8th day of June, A. D. 1948.

THOMAS F. MURPHY,

Assistant (l'ommz'ssz'oner of Patents. 

